Does your A/C system cool down your house efficiently? This is a very simple and fairly accurate method to figure that out.
1. Make a note of your current indoor temperature
2. Turn on your A/C system and put a thermometer at a supply vent and let the A/C run for 5-10 minutes.
The temperature of the air coming out of your supply vent should be between 14-22F cooler than your current indoor temperature.
The temperature of the air coming out of your supply vent should be between 14-22F cooler than your current indoor temperature (Some say between 15-20F).
HOW TO UNDERSTAND THE RESULTS
Differential is within the recommended range
If the differential is within the recommended range your system appears to be running properly.
Differential is below the recommended range
If the differential is below the recommended range your system is not operating properly which will increase the cost of cooling your house.
Servicing the A/C system may be necessary.
Differential is above the recommended range
If the differential is above the recommended range it could indicate that the furnace filter is dirty or that the system is improperly sized.
Servicing the A/C system may be necessary.